TB 9-4931-489-50
MCL 15009 or Microdot M447, MIS-10240; Power
b. Procedure. Calibrate thermistor mount with power
Measurement System, NBS Type 11, 6625-531-4331 (2
standard assembly, using TB 9-6625-1932-35 at one fre-
each); Thermistor Mount, H-P 478A, 7910461 (2 each);
quency. Value determined must agree with value indicated
and Digital Voltmeter, Dana 5703-S-2127, 792606.
on thermistor mount within 4 percent.
b. Procedure. Compare power output of NBS-1 with
14. Directional Couplers. Intercompare Directional
power input of NBS-2 at 300 MHz. Agreement must be
Couplers NBS-1 and NBS-2.
within 2.4 percent. Compare power output of NBS-2
a Equipment. Directional Coupler, DC 1/350C-AR,
with power input of NBS-1 at 300 MHz. Agreement must
NBS-1 and Directional Coupler, DC1/341D-AR, NBS-2.
Additional equipment required: RF Power Generator, be within 2.4 percent
SECTION IV
8
